The present invention relates to electron tubes and particularly to a tube-base assembly having improved high voltage stability between electrically conductive pins.
Electrical connection to internal components in an electron tube is usually made through conductive pins which extend through the glass envelope of the tube. In a cathode ray tube, these pins extend from the end of the tube neck and are protected by a tube base. Generally, tube bases are formed of hard plastic material which abuts the tube neck. The pins pass through apertures in the base whereby the base adds stiffness and strength to the pins as well as providing insulation between the pins.
In the past, bases have been glued to the tubes so that they would remain fixed regardless of the number of times the bases might be inserted into or removed from their associated sockets. However, it has been found that a cost reduction can be realized if the bases are force-fit onto the pins without use of an adhesive. Unfortunately, with use, a force-fit base may loosen and become somewhat spaced from the tube envelope. When some separation of the base does occur, there is a gap in the insulation between pins. Because of the gap, arcing between a high voltage conducting pin and a lower voltage conducting pin can develop. Such arcing is extremely undesirable.